Improvement in clamps



fw. H, PAYNE L H. Imhof. Clamps. N0. 142,938. PatentedSeptember,1813.

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WILLIAM H. PAYNE AND HENRY IMHGF, 0F LOOKPORT, NEW YORK.

IMPROVEMENT IN CLAMPS.

Specication. forming part of Letters Patent No. 142,938, dated September16, 1873 application led June 28, 1873. i

To all whom it may concern Be it known that we, WILLIAM H. PAYNE andHENR y MHoF, of Lockport, in the county of Niagara and State of NewYork, have invented a new and valuable Improvement in Glam ps 5 and wedo hereby declare that the following is a full, clear, and exactdescription of the construction and operation of the same, referencebeing had to the annexed drawings making a part of this specitication,and to the letters and figures of reference marked thereon.

Figure l of the drawings is a representation or" our improvedcramp-head, by an elevation. Fig. 2 is a detailed view of the same.

Our invention has relation to cramp-heads Nfor carpenters andcabinet-makers; and the novelty consists in the construction andarrangement ofthe parts, hereinafter more fully described and claimed.The object of our invention is to make a very durable cramp-bar, whichis easily managed, and may be applied to a greater variety of work thanthe crampbar ot' old construction.

In the drawings, A represents a stretcher or cramp bar; B, thefoot-block, connected therewith by a square metallic link, C, fast enedto the said foot-block by passing it through the hole c and then weldingthe ends together. The said link C engages in one of the notches a inthe lower side ot' the crampbar, and thereby holds the foot-block Blirmly to the bar A. The head-block D is constructed of metal, andconsists of a head with a square hole, into which the bar A is fitted sothat it may slide through, and to which the said bar is fastened by akey or wedge, d. With this head D the boss D is connected, which isprovided with an inside screw-thread, into which a hand-screw, E, isfitted. The screwT E is made of wood, and is provided with a metal cap,F, at its end e, which cap receives the foot e in a socket, f, and isfastened to it by an axial screw, f', so that the foot e, lin wearingoft' its substance against the said socket, will wear centrally andnever lose its lateral t.

The old cramp-heads have to be permanently fastened to the stretchers,as the nature of the material forbids the use of wedges for very securefastening. The inconvenience arising therefrom is this, that everystretcher has to be provided with a head 5 and, unless a tradesman has alarge variety of cramp-heads with bars of different lengths, he iscompelled to bny those heads with the longest bars or stretchers, to dolong and short work with them.

/Ve lit a set of stretchers of different lengths into the head D, whichcan in a very short time be attached to any of them, and after havingbeen use d may just as easily be detached and put in a safe place.

We make the set-screw E of wood, because it has a decided advantage overmetal of the same torsional strength by its great longitudinalsteadi'astness. Another advantage is that of cleanliness, which, onaccount of the necessary lubrication, eannot be obtained with metalscrews.

What we claim as new, and desire to secure by Letters Patent, is

The cramp head described, having the wooden screw E, provided with metalcap F at its end e, the adjustable metal head D, with the wedge d, andthe cramp-bar A, substantially as shown and described.

In testimony that we claim the above we have hereunto subscribed ournames in the presence of two witnesses.

` WM. H. PAYNE. HENRY IMHOF.

'Vitnesses SAMUEL Soo'ir, WM. JonNsoN.

